<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style> 
        select {
            width: 200px;
            height: 300px;
            font-size: 22px;
            background-color: #80ff45;
        }
    </style>
</head>
<script src="../jquery-3.5.1.js"></script>
<body>
    
    <select name="" id="sel1" size="4" multiple>
        <option value="">香蕉</option>
        <option value="">大鸭梨</option>
        <option value="">苹果</option>
        <option value="">大西瓜</option>
    </select>

    <button>&gt;&gt;&gt;</button>
    <button>&lt;&lt;&lt;</button>
    <button>&gt;</button>
    <button>&lt;</button>

    <select name="" id="sel2" size="4" multiple>123</select>
    <script>
 
        $(function(){
            $('button').eq(0).click(function(){
                $('#sel2').append($('#sel1>option'))
            })
            $('button').eq(1).click(function(){
                $('#sel1').append($('#sel2>option'))
            })
            $('button').eq(2).click(function(){
                $('#sel2').append($('#sel1>option:selected'))
            })
            $('button').eq(3).click(function(){
                $('#sel1').append($('#sel2>option:selected'))
            })
        })
    </script>
</body>
</html>